[PATCH 1/3] [PATCH] af9035: Better explain how i2c bus speed is computed.

Gon Solo
2019-10-03T12:45:48Z

Original patch from Mauro Carvalho Chehab.

Signed-off-by: Gon Solo <gonsolo@gmail.com>
---
drivers/media/usb/dvb-usb-v2/af9035.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/media/usb/dvb-usb-v2/af9035.c b/drivers/media/usb/dvb-usb-v2/af9035.c
index 3afd18733614..7828f8567da0 100644
--- a/drivers/media/usb/dvb-usb-v2/af9035.c
+++ b/drivers/media/usb/dvb-usb-v2/af9035.c
@@ -1197,6 +1197,9 @@ static int af9035_frontend_attach(struct dvb_usb_adapter *adap)
return ret;
}

+/* I2C speed register = (1000000000 / (24.4 * 16 * I2C_speed)) */
+#define I2C_SPEED_REGISTER 7
+
static int it930x_frontend_attach(struct dvb_usb_adapter *adap)
{
struct state *state = adap_to_priv(adap);
@@ -1208,13 +1211,13 @@ static int it930x_frontend_attach(struct dvb_usb_adapter *adap)

dev_dbg(&intf->dev, "adap->id=%d\n", adap->id);

- /* I2C master bus 2 clock speed 300k */
- ret = af9035_wr_reg(d, 0x00f6a7, 0x07);
+ /* I2C master bus 2 clock speed ~300k */
+ ret = af9035_wr_reg(d, 0x00f6a7, I2C_SPEED_REGISTER);
if (ret < 0)
goto err;

- /* I2C master bus 1,3 clock speed 300k */
- ret = af9035_wr_reg(d, 0x00f103, 0x07);
+ /* I2C master bus 1,3 clock speed ~300k */
+ ret = af9035_wr_reg(d, 0x00f103, I2C_SPEED_REGISTER);
if (ret < 0)
goto err;

--
2.20.1